An investigation into the mysterious death of an Ohio teen has highlighted the risks of caffeine powder.

Logan Stiner, 18, died May 27 from what health officials are calling a caffeine overdose, the Associated Press reported.

The high school senior from LaGrange, Ohio, had 70 micrograms of caffeine per milliliter of blood in his system, according to Loraine County coroner Stephen Evans. A typical coffee drinker would have 3 to 5 micrograms.

After the teen’s sudden death, his mother found bags of caffeine powder in his room, the AP reported.

The brands of the powder were not disclosed, but several brands of caffeine powder are sold online. And since the powder is sold as a dietary supplement, it’s not subject to the same U.S. Food and Drug Administration regulation that governs caffeinated drinks.

The caffeine limit in soda, for example, is 200 milligrams per serving according to FDA. The same caffeine dose is present in 1/16th of a teaspoon of caffeine powder, according to Evans. However, since the caffeine powder is not regulated by the FDA, it is difficult to know the exact concentration of caffeine in different brands of caffeine powders.

Evans said the powder would be difficult to take safely without a measuring device, since even a small amount could be more than a safe dose. According to Evans, a single teaspoon could be equal to 16 cans of highly caffeinated soda.

"You'd have to be a chemist to figure out how much to put in so that you're not in a lethal amount," Evans said. "You'd have to really know what you were doing and have scales.”

Evans said he was “perplexed at first” by Stiner’s unexpected death.

"Because why does a young, healthy person suddenly have a cardiac arrhythmia and a seizure and die?” he told the AP.
Stiner died a week before his high school graduation ceremony, shortly after being crowned prom king.

While reactions to caffeine can vary widely from person to person, toxicologists generally warn that ingesting 5 to 10 grams of the stimulant could be lethal. However, one case study found that a 41-year-old woman survived after ingesting 50 grams of caffeine.

"It is very difficult to predict one's response to caffeine. Some people are more sensitive than others," said Bruce Goldberger, the director of toxicology at the University of Florida College of Medicine, told ABC News in 2012. "Therein lies the problem. If someone has an undiagnosed medical condition, they may ingest caffeine not knowing it may have a deleterious effect, such as a cardiac arrhythmia, hypertension or anxiety."

In a statement to ABC News today, the FDA said it has “repeatedly voiced concern about products with high concentrations of caffeine” and is carefully monitoring new caffeinated products.